How to Use a Systematic Literature Review and Meta-Analysis

Abstract

This article introduces practicing urologists to the critical appraisal of systematic reviews and meta-analyses to guide their evidence-based clinical practice. Using a urological clinical case scenario we introduce a 3-step process in evaluating systematic reviews and meta-analyses by considering 1) the validity of the review results, 2) what the results are, and 3) the extent to which the results can and should be applied to patient care. A systematic review seeks to synthesize the medical literature about a specific clinical question using explicit methods to perform a comprehensive literature search, identify and select eligible studies, critically appraise their methods, and judiciously summarize the results considering how they vary with study characteristics. When this summary involves statistical methods, ie a meta-analysis, reviewers can offer a pooled estimate that will have greater precision and will apply more broadly than the individual studies. The quality of the underlying studies, the consistency of results across studies and the precision of the pooled estimate can considerably affect the strength of inference from systematic reviews. Valid systematic reviews of high quality studies can increase the confidence with which urologists and patients make evidence-based decisions. Thus, urologists need to recognize the inherent limitations, understand the results and apply them judiciously to patient care.